Art Shuler wrote:-
>Does anyone know of a way to completely eliminate gold slivers on a PWB
>which is manufactured using a selective gold process? We realize due to
>the etch factor, that there will be a 1.4 mil outgrowth when etching 1
>oz. copper cladded material.

I don't think you can get rid of them once they are present, but you can
minimise their formation. Use thinner 0.5oz base copper and plate up the
extra copper before gold. Also if you are using an ammoniacal etch, make
sure the pH is at the low end of the scale around 8.2 which should not
affect the speed but will reduce the undercut.

It is difficult to eliminate this problem and the best route is to go
for an alternative post etch finish. I can't think of a good reason why
an electro-plated hard gold finish should be specified these days with
all the other finishes available.

Good luck
Paul Gould
[log in to unmask]
Teknacron Circuits Ltd
Isle of Wight,UK

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
##############################################################